(A) Western blot analyses of total cell lysates. Cells stably expressing pTRIPZ-dox-shMort (dox-shM) were treated with doxycycline (0.5 μg/mL) for 3 days, and then co-treated with dox and 100 nM AZD6244 (AZD), 1 μM SCH772984 (SCH), or the vehicle control DMSO for 2 days before harvest. C-lamin A indicates cleaved lamin A. β-actin is the control for equal protein loading. Densitometry shown in supplemental figure S5. (B) TO-PRO 3 assays of cells treated as described in (A). (C) Calcein assays of cells treated as described in (A). Representative FACS histograms are shown in supplemental figure S6. Data are means ± SEM, n = 3. P values are relative to dox-treated DMSO control. * P < 0.05, ** P < 0.01, and *** P < 0.001 by two-way ANOVA with Bonferroni post-tests.